1.Identification and Molecular Analysis of H5N2 Subtype Highly Pathogenic Avian Influenza Virus Isolated From Goose
Chunguo LIU ; Ming LIU ; Yun ZHANG ; Dafei LIU ; Weiqi PAN ; Encheng SUN ; Jinling DU ; Hongtao LI
Progress in Biochemistry and Biophysics 2006;0(01):-
A H5N2 subtype avian influenza virus isolated from goose belongs to highly pathogenic avian influenza virus, and the intravenous pathogenicity indexes (IVPI) =2.99. But ducks are not sensitive to this isolated influenza virus. The virus can infect mouse but only replicates in lung and has no pathogenicity. HA and NA gene of this isolated strain share 99.4% and 99.8% nucleotide sequence identity to the HA gene of A/chicken/Hubei/ 489/2004 (H5N1) and the NA gene of A/chicken/Jilin/53/01 (H9N2), and share 99.3% and 99.6% amino acid sequence identity to the HA protein of A/chicken/Hubei/489/2004 (H5N1), A/swan/Guangxi/307/2004 (H5N1), A/wild duck/ Guangdong/314/2004(H5N1), A/chicken/Henan/210/2004(H5N1) and the NA protein of A/chicken/ Jilin/53/01 (H9N2). There are several continuous basic amino acids (-RRRKKR-) at the cleavage site of HA protein. Phylogenetic trees analysis of HA and NA gene suggests that the isolated influenza virus probably originated from the reassortment of H5N1 and H9N2 subtype influenza virus.
2.Applications of reverse genetics in studying classical swine fever virus.
Dafei LIU ; Yuan SUN ; Huaji QIU
Chinese Journal of Biotechnology 2009;25(10):1441-1448
Classical swine fever (CSF), caused by classical swine fever virus (CSFV), has been epidemic or endemic in many countries, and causes great economical losses to pig industry worldwide. Attenuated vaccines (such as C-strain) have played an important role in the control of CSF. Recently some new phenomena appear, such as atypical and persistent infections of CSF, immunization failure and so on. Meanwhile, eradication programs have been implemented in many countries, restricting the widespread applications of attenuated vaccines. Thus, currently the priority is to strengthen the research in pathogenesis and transmission mechanisms, as well as to develop marker vaccines. Recently, the applications of reverse genetics technology open up a new way for research of structure and function of CSFV proteins and development of novel vaccines against CSF. This review focuses on the progress of applications of reverse genetics in the functional analysis and marker vaccine development of CSFV, and also discusses the problems confronted now and prospective aspects in the study of CSFV.
Classical swine fever virus
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genetics
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Cloning, Molecular
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Genetics, Microbial
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methods
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RNA, Viral
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genetics
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Recombination, Genetic
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Vaccines, Synthetic
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biosynthesis
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immunology
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Viral Vaccines
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biosynthesis
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genetics
3.Identification and targets prediction of snoRNAs in α-particle induced carcinogenesis of human branchial epithelial cells
Xiaoqiao YUE ; Chenjun BAI ; Dafei XIE ; Xiaodan LIU ; Pingkun ZHOU
Chinese Journal of Radiological Medicine and Protection 2020;40(6):413-419
Objective:To identify the differentially expressed snoRNAs in the carcinogenesis of cells induced by α-particles radiation and predict the targeted genes and RNA-co-expression networks.Methods:Full transcriptome expression microarray biochips were employed to screen the differentially expressed snoRNAs between human bronchial epithelial BEP2D cell line and its derivative malignantly transformed cell line BERP35T-4 established by α-particle irradiation. The expression changes of snoRNAs and their derived sdRNAs were confirmed by qRT-PCR. The functional domains, targets and co-expression networks of snoRNA were predicted by bioinformatics analysis.Results:Consistent with the result of microarray assay, the expression changes of the screened snoRNAs were confirmed by qRT-PCR. The expressions of sno116 family decreased in BERP35T-4, which was 0.105% ( t=26.60, P<0.01) of BEP2D, and they were generally down-regulated in radiation-induced carcinogenic BERP35T-4 cells and the human lung cancer cell lines A549 and H1299. It was also found that the expression level of the sdRNAs derived from sno116-14 was significantly different in the same cells. It was speculated that these less expressed sdRNAs of sno116-14 could be due to degradation as the consequence of interaction with their targets. The co-expression networks of sno116 family with other types of RNA were established, and the predicted targets of sno116-14 included ZNF280D, TFDP1, CCDC28B, RPS6KA3, CANX, RUNX1 and KALRN, which were related to the functions of cell proliferation and cytoskeletal structure. Conclusions:Some differentially expressed snoRNAs related to α-particle induced carcinogenesis have been identified. It is predicted that the target gene of sno116-14 is involved in the biological processes such as cell proliferation, cytoskeletal structure and the signaling pathways for function regulation, providing new information for the function model of C/D box snoRNAs and the mechanism of radiation carcinogenesis.
4.A prime-boost vaccination strategy using a Semliki Forest virus replicon vectored DNA vaccine followed by a recombinant adenovirus protects pigs from classical swine fever.
Yuan SUN ; Dafei LIU ; Yufei WANG ; Na LI ; Hongyu LI ; Bingbing LIANG ; Huaji QIU
Chinese Journal of Biotechnology 2009;25(5):679-685
We have previously evaluated a Semliki Forest virus (SFV) replicon vectored DNA vaccine (pSFV1CS2-E2) and a recombinant adenovirus (rAdV-E2) expressing the E2 glycoprotein of classical swine fever virus (CSFV) in pigs. The results showed that the immunized pigs were protected from virulent challenge, but few pigs showed short-term fever and occasional pathological changes following virulent challenge. To enhance the immunogenecity of the vaccines, we tried a prime-boost vaccination strategy using a combination of prime with pSFV1CS2-E2 followed by boost with rAdV-E2. The results showed that all the immunized pigs developed high-level CSFV-specific antibodies following prime-boost immunization. When challenged with virulent CSFV, the immunized pigs (n = 5) from the heterologous boost group showed no clinical symptoms, and CSFV RNA was not detected following challenge, whereas one of five pigs from the homologous boost group developed short-term fever and CSFV RNA was detected. This demonstrates that the heterologous prime-boost vaccination regime has the potential to prevent against virulent challenge.
Adenoviridae
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genetics
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metabolism
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Adenovirus E2 Proteins
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genetics
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immunology
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Animals
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Classical Swine Fever
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immunology
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prevention & control
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Classical swine fever virus
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genetics
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immunology
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Genetic Vectors
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Immunization, Secondary
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Replicon
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genetics
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Semliki forest virus
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genetics
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metabolism
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Swine
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Vaccines, DNA
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immunology
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Viral Envelope Proteins
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genetics
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metabolism
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Viral Vaccines
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immunology